Water-insoluble azo dyestuffs



Patented June 14, 1938 UNITED STATES PATENT. OFFIQE WATER-INSOLUBLE AZODYESTUFFS Grald Bonhote, Basel,

The firm of Society Switzerland, assignor to of Chemical Industry inBasle, Basel, Switzerland No Drawing. Application October 10, 1936, Se-

rial No. 105,150. In Switzerland October 23,

Claims.

azo-compound of the aryl esters of the 2-amino-- 5 benzoic acid withvarious coupling components,

particularly with arylides of 2,3-hydroxynaphthoic acids, new dyestuffsare obtained which may be characterized by excellent properties offastness. If sulfonated coupling components have been used there areobtained wool or cotton dyestuffs according to the selection of thesecomponents. If unsulfonated coupling components have been used there areobtained lacquer or pigment dyestuffs which, when produced on suitablesubstrata, dye the same very valuable tints. Among these insolubledyestuffs those are particularly valuable which are produced with aid ofsuch arylides of 2,3-hydroxynaphthoic acids which are obtainablethemselves by condensation of 2,3-hydroxynaphthoic acid 'with aromaticamines of the benzene and naphthalene series. They correspond to thegeneral formula in which R1 stands for an aryl nucleus of the benzeneseries and R2 stands for an aryl nucleus of the group consisting of arylnuclei of the benzene and naphthalene series. Among those dyestufisthose are particularly valuable which derive from such arylides of2,3-hydroxynaphthoic acid which are produced themselves with aid ofaromatic-amines of the benzene series, particularly ifthe aromaticamine, such as ortho-anisidine or ortho-phenetidine contains an alkoxygroup in ortho-position to the NHa-group, and in which as diazotizingcomponent the parachlorophenol ester of the ortho-aminobenzoic acid isused. These particularly valuable dyestuffs correspond therefore to thegeneral formula in which R2 stands for an aryl nucleus of the benzeneseries which is substituted in ortho-position to the NH-group by analkoxy group selected itself from the group consisting of OCHa andOC2H5.

Ifhe following examples illustrate the invention:

Example 1 24.8 parts by weight of para-chlorophenyl ester ofZ-aminobenzoic acid are diazotized as usual and the diazo-compound isintroduced into a solution of 26.3 parts of 2,3-hydroxynaphthoic acidortho-anisidide, 40 parts of caustic soda solution of 30 per cent.strength, parts of sodium carbonate and 1000 parts of water. Thedyestuff thus formed is immediately precipitated. The orange precipitateis filtered and dried. The new dyestuff corresponds to the formula OCHaSimilar dyestuffs are obtained when replacing the para-chlorophenylester of Z-aminobenzoic acid by the phenyl ester, the various cresylesters, the ortho-chlorophenylester, and the like, of the1,2-aminobenzoic acid.

Example 2 Cotton yarn is impregnated with a solution of 7 grams of2,3-hydroxynaphthoic acid-2'- methoxy anilide, 12 cc. of caustic sodasolution of 34 B., 10 cc. of Turkey red oil and 7 cc. of formaldehydesolution of 40 per cent. strength, per litre; it is then wrung out anddeveloped in the presence of aluminium sulfate in a diazo-solutionbuffered with sodium acetate and corresponding with 2 grams of thepara-chlorophenyl ester of 2-aminobenzoic acid, per litre. There isproduced a pure orange tint of excellent properties of fastness. Withthe 5-chloro-2-anisidide of the 2,3-hydroxynaphthoic acid there areobtained somewhat more reddish dyeings having These two dyestuffs OCH:

Further orange tints are obtained with other arylides of2,3-hydroxynaphthoic acid, for example with the paraand meta-toluidides,the 4-ch1oro-2-toluidide, the 5-chloro-2-anisidide, the5-chloro-2-toluidide and the orthoand meta-chloranilide.

Scarlet red tints are obtained with the parachloranilide, the aandfi-naphthylamide, the para-anisidide, the para-phenetidide; and redbrowntints with the Z-methyll-methoxyanilide and the2,4-dimethoxy-5-chloranilide of 2,3- hydroxynaphthoic acid.

Similar dyestufis are further obtained when coupling on the fiber thearylides of 2,3-hydroxynaphthoic acid mentioned in these examples withother diazotized aryl esters of 1,2-aminobenzoic acid, such as forexample the phenyl ester, the cresyl esters, theortho-chlorophenylester, and the like.

Similar tints are produced in printing or on the piece.

What I claim is:-

1. The azo-dyestufis obtained from diazotized aryl esters oforthoaminobenzoic acid and corresponding to the general formula in whichR1 stands for an aryl nucleus of the benzene series and R2 stands forsuch an aryl nucleus of the benzene series which is substituted inortho-position to the NH-group by an alkoxy group selected itself fromthe group consisting of OCH; and. OCzI-Is, which products are orange tored powders insoluble in water and which, when produced on the vegetablefiber, dye the same fast orange to red tints.

2. The azo-dyestufis obtained from diazotized aryl esters ofortho-aminobenzoic acid and corresponding to the general formula inwhich R2 stands for an aryl nucleus of the benzene series which issubstituted in orthoposition to the NH-group by an alkoxy group selecteditself from the group consisting of OCHs and OCzHs, which products areorange powders insoluble in water and which, when produced on thevegetable fiber, dye the same fast orange tints.

3. The azo-dyestuffs obtained from diazotized aryl esters ofortho-aminobenzoic acid and corresponding to the general formula whichproduct is an orange powder which, when produced on cotton dyes the samefast orange tints.

5. The azo-dyestuff of the formula H O=O Cl which product is an orangepowder which, when produced on cotton dyes the same fast orange tints.

GERALD BoNHoTE.

